Forex position size calculator: lots, units and risk

Account balanceIn your account currency

Risk asA share of the balance or a fixed amount, your own figure either way

Risk per trade (%)Your own figure; the calculator does not suggest one

Amount at riskIn the account currency; your own figure

Stop distance (pips)From the entry to the stop; decimals are fine

Pip size0.01 when the pair is quoted in Japanese yen

Your account currency isHow a pip in the quote currency becomes money in your account

Exchange rate of the pairQuote currency per 1 base unit, such as 1.0850; needed when the account is in the base currency, optional otherwise (for the notional)

Quote currency in your account currencyAccount currency per 1 unit of the quote currency, such as the GBP/USD rate for EUR/GBP in a USD account

Pip value per lotIn the account currency, as your platform shows it

Units per lot100,000 for a standard forex lot; check your platform's contract size

Lot stepThe smallest lot increment on your platform, such as 0.01; 8 decimals if empty

Position size, rounded down to the lot step—

Units—

Exact size before rounding—

Amount at risk—

Loss at the stop with the rounded size—

Pip value per lot—

Pip value of this position—

Notional value in the account currency—

Notional ÷ balance (effective leverage)—

All default values are hypothetical and are not a suggested risk or stop. Leveraged forex carries high risk: a stop can fill beyond its price, so a real loss can exceed the amount shown, and spread, commission and swap are not included.

How to calculate position size in forex

The position size that keeps the loss at your stop to the amount you chose is that amount divided by what one lot loses over the stop distance. The calculator uses these formulas:

Amount at risk = balance × risk per trade ÷ 100, or a fixed amount you type

Pip value per lot = units per lot × pip size × value of one quote-currency unit in your account currency

Lots = amount at risk ÷ (stop distance in pips × pip value per lot)

Units = lots × units per lot

The lots are rounded down to your platform's lot step, so rounding never takes the planned loss above the amount at risk. The pip value per lot is the same arithmetic as in the pip calculator, which shows it on its own.

Worked example

For EUR/GBP the exact size is 0.315 lots; rounded down to the 0.01 step it is 0.31, so the planned loss stays a little under 100.

Turning a pip into your account currency

A pip is counted in the quote currency, the second currency of the pair, so it has to be converted unless your account is held in that currency.

• Account in the quote currency (EUR/USD in a USD account): one pip of a standard lot is 10 units of the account currency and no rate is needed.
• Account in the base currency (USD/JPY in a USD account): the pip is 1,000 yen per lot, which is divided by the pair's rate. At 150.00 that is 6.6667 USD, and the figure moves with the rate.
• Neither (EUR/GBP in a USD account): the pip is 10 GBP per lot, multiplied by what one GBP is worth in USD, the GBP/USD rate.
• Typed pip value: if your platform shows the value of one pip per lot, enter it instead.

The page fetches no prices: every rate is typed by you, so use the rate at the time you size the trade.

Lots, units and the lot step

A standard forex lot is usually 100,000 units of the base currency, a mini lot 10,000 and a micro lot 1,000, so 0.40 standard lots are 4 mini lots or 40 micro lots.

Platforms set this per symbol. MetaTrader 5's contract specification defines the contract size as the number of units in one lot and lists a minimal volume and a volume step, the increment that order sizes move in. Enter both from your own platform. If the size rounds down to zero, the amount at risk does not cover one lot step at that stop distance, and the calculator says so.

What the result leaves out

The result is the planned loss at the stop price and nothing more.

• Slippage and gaps: in a fast market, or when the price jumps over a weekend, a stop can fill well beyond its price.
• Costs: the spread, any commission per lot and overnight swap can add to the loss.
• Margin: the notional row shows how large the position is next to the balance. Leverage limits depend on where you trade: ESMA set 30:1 for major currency pairs for retail CFD clients in 2018 and said 74–89% of retail accounts typically lose money, and in the United States retail forex leverage is set through security deposits within limits the CFTC provides.

This page suggests no risk percentage, stop distance or leverage, and Fincode does not manage accounts.

Which values to enter

• Balance: in your account currency.
• Risk as a percentage or an amount: your own figure either way.
• Stop distance: in pips from the entry to the stop; decimals are fine.
• Pip size: 0.01 for pairs quoted in Japanese yen, 0.0001 for most others.
• Account currency and rates: pick how your account currency relates to the pair, then type the pair's rate and, for a cross, the conversion rate, or your platform's pip value per lot.
• Units per lot and lot step: from your platform's contract specification.

Frequently asked questions

How do I calculate lot size in forex?

Divide the amount you choose to risk by the stop distance in pips times the pip value of one lot. With 100 at risk, a 25-pip stop and 10 per pip per lot, that is 0.40 lots, or 40,000 units.

What is the pip value of one standard lot?

100,000 units × 0.0001 is 10 units of the quote currency, or 1,000 for a yen-quoted pair at 0.01. In a USD account that is 10 USD on EUR/USD, and about 6.67 USD on USD/JPY at a hypothetical rate of 150.00.

What percentage of my account should I risk per trade?

This page recommends none. The calculator turns the figure you choose into a size; the choice is yours, and a stop may fill worse than its price.

Does leverage change the position size?

Not in this calculation: the size follows from the amount at risk and the stop. Leverage decides how much margin the position ties up, and the notional ÷ balance row shows how large the position is next to the account.

Why can my loss be bigger than the amount at risk?

A stop can fill beyond its price in a fast market or after a gap, and the spread, commission and swap can add to the loss. The result shows the planned loss at the stop price only.

Sources

• MetaTrader 5 Help: Market Watch, contract specification (contract size, volume step) (opens in a new tab)
• ESMA: ESMA agrees to prohibit binary options and restrict CFDs to protect retail investors (27 March 2018) (opens in a new tab)
• CFTC: Foreign currency trading, retail forex rules (opens in a new tab)

This calculator is general information, not tax, legal or investment advice. Results depend on the values you enter; fees, margin rules and tax rules differ by exchange and country and change over time, so check the official source and ask a licensed adviser about your own situation. Sources, checks and corrections: see the editorial policy.